The man behind the voiceover has never been identified. One popular candidate is David Suchet, but he has no memory of doing it.
The show’s theme is by Cyril Ornadel, who also composed the song “If I Ruled The World”, covered by Tom Jones, James Brown and more.
None of the stories have titles – any you may see are fan inventions. The adventures are commonly referred to as Assignments One to Six.
In 2015 it was announced that Luther creator Neil Cross is working on a revival of the show, emphasising the horror elements.